From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E583647C10D; Mon, 28 Sep 2026 21:01:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790629319; cv=none; b=mViwVerot5ja0gWg2LFsXGl++NpNJqv9WMjJsqJR7e2op4DV1+xmx/Q//mnQZ4Ix4r628HgYcMFDgU2OdfWWPk6LyI2GrcMJ3nTL4nY/z/g+aHdv8/9FuJ9Q/jZEy1tsAXR4uhIAA55MtNM0LxiM7Xi15JXR2dLW3lgtsLjnxZ4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790629319; c=relaxed/simple; bh=/npj3zdP2RbC2CIoCxwIFftfUISIBxvHaVXvjpZDXWo=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=efp82zGtxRBS2erz8XdbltdEFIbuHw78fgi5fZMLBekdi8LAvEsl66iPROswtbA7F1U6DNz2OEGnlehWB3e4L3UBZLoMNF7gNhXMEdgoklZt5TRTjAr3aM29u4B+H1qucSv7+OiVzVJQU8MHYU9A2ZpcfukSl/7DTp9Dyf5uQjM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=H3lKCrs8; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="H3lKCrs8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27A071F000FF; Mon, 28 Sep 2026 21:01:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790629317; bh=fR85tYcpWQ8ox9kILOPgK1wQGVXd4jwMDchSGmBsxeA=; h=Date:From:To:Cc:Subject:In-Reply-To; b=H3lKCrs8OLzD6PYZhjlxHmjVpkC8QKLbXJfkZUgRYy29aPCBc/igzbj8NZcCt2jmK kqlRSLb98InAPQPm6wu3AEOiTnrAdpXtzlHKAoWbyk9v2sjTzs1vhTdERVys+A6iW8 zJp2TcZLCgH9iedmz7gqueL1UleilN7KsQHv8gxS/rSuZbhThT8sI+OcGWlfmFekIr 9vl7vs9jVO8vBqevuUlpc5igDrBXN5SuXaZE4TE9m6VKiJuKNPfKJzIfGZuAWfq4bu 6qRJKmhAgYjhwAQNTWNMt3Ya/3QZLoXO9GSD4kqGGmq9vIGgbAjubwil079kfXHGlR EwF2+eS7ZEcRg== Date: Mon, 28 Sep 2026 16:01:55 -0500 From: Bjorn Helgaas To: Marek Vasut Cc: linux-pci@vger.kernel.org, Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Bjorn Helgaas , Conor Dooley , Geert Uytterhoeven , Krzysztof Kozlowski , Lorenzo Pieralisi , Manivannan Sadhasivam , Rob Herring , Yoshihiro Shimoda , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org Subject: Re: [PATCH v5 6/6] PCI: dwc: rcar-gen4: Add support for R-Car X5H PCIe4 Message-ID: <20260928210155.GA2260978@bhelgaas> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260921202823.72620-7-marek.vasut+renesas@mailbox.org> On Mon, Sep 21, 2026 at 10:27:48PM +0200, Marek Vasut wrote: > Add support for R8A78000 (R-Car X5H) PCIe4. > > This driver previously supported R-Car Gen4 S4/V4H/V4M. PCIe features > of R-Car X5H PCIe4 are almost all the same. > > The controller initialization sequence is slightly different and is > factored out into controller specific callbacks, in a manner similar > to previous R-Car Gen4 handling. > > The controller does have a PHY attached to it, but the PHY is operated > by a separate PHY driver, the PHY driver instance binding is handled > in rcar_gen4_pcie_get_resources() and controlled in the aforementioned > controller specific callbacks. > > The controller driver is deliberately using "renesas,rcar-gen5-pcie4" > DT compatible string to discern R-Car X5H PCIe4 controller supported > by this driver, from R-Car X5H PCIe6 controller which will most likely > use a separate driver. The gen5/pcie4 usage is confusing. I often push back on things like "PCIe Gen4" because it's ambiguous (does it mean "compliant with base spec r4.0" or "supports 16 GT/s" or something else), but it's so widely used to mean transfer rate that it's hard to resist, and the best I can hope for is clarification. But in "renesas,rcar-gen5-pcie4", I don't know what the 5 and the 4 mean. Maybe "gen5" refers to some internal R-Car thing, and "pcie4" is something like "PCIe Gen4, i.e., 16 GT/s"? > The R-Car X5H PCIe4 controller embeds HDMA instead of EDMA embedded > in the R-Car Gen4 PCIe controller, "dw-edma" driver supports both > DMA variants. > > Endpoint mode is currently not implemented for R-Car Gen5 PCIe4.